Some computer systems utilize a mainframe or host server computer for supporting a number of simultaneous users in a computer network. Users access data on the host server through connected computer terminals over the network. In order to access the data on the host server computer, the terminal computers are used to connect to and communicate with the host server over the network using a terminal emulation software program such as Telnet. The Telnet program runs on each terminal computer and enables the terminal computer to connect to the host server to establish a host session. Once a host session is established, users may enter commands through the Telnet program which will then be executed as if the user were entering them directly on a screen of the host server. For example, when logging on to the host server to establish a host session the terminal emulation software may be programmed to expect the password field to start at a specific character position on the host logon screen. Thus, once the appropriate password is received by the terminal emulation software, the password is entered as data in the corresponding password field on the host logon screen of the host server.
Periodically, the software running on the host server computer may be updated or modified resulting in changes in formatting of the host screens. These changes may affect the manner in which commands from a connected terminal computer are interpreted such that data specified for a previously defined field on a host screen may no longer be valid for that field. As a result, the host server may no longer recognize the command from the terminal computer and returns an error to the connected terminal computer. For example, the host server will return an error if the password has changed such that a current password entered by the terminal emulation program is no longer valid.
One previous method for maintaining screen changes on host servers requires modifying and recompiling the code in the terminal emulation program. However, modifying and recompiling the terminal emulation program code is often a time-consuming process and requires additional testing, which is often a time-consuming process requiring skilled programming knowledge. Moreover, this method may also require additional testing of the recompiled code to verify that the appropriate modifications have been made. Another previous method for maintaining screen changes requires the use of “screen scraper” programs in which the actual host screens are recorded to capture the changes. However, in most cases such “screen scraper” programs are platform dependent, that is, they require a specific computer operating system in which to operate. Furthermore, the use of “screen scraper” programs requires a user to manually review each captured host screen to locate where the error has occurred making their use inconvenient during automated or mechanized processes.
It is with respect to these considerations and others that the present invention has been made.